242 POWER DISTRIBUTION FOR ELECTRIC RAILROADS. 
car. 'The normal speed is from twenty to thirty miles per 
hour 11 regular service, and the system has proved entirely 
reliable. 
For this heavy special or suburban service electric 
power 1s singularly well suited. It does the work well, at 
high efficiency and at moderate cost. - Basing an estimate 
of cost on a normal two-car train, requiring eighty kilowatts 
while running and allowing for thiseighty kilowatts average 
output at the station, we can figure readily the cost of power 
per train mile. The train makesan average of about twenty 
miles per hour. It thus demands four kilowatt hours per 
train mile. The service is twenty hours per day, and the 
  
average load fairly high, probably about half the maxi- 
mum. On this basis the power per train mile should not 
cost, delivered on the line at the station, more than six 
cents, including station charges of every sort and kind. 
Two cents additional should cover all charges for the de- 
livery of the power, including the motors. FEven more 
unfavorable conditions than those assumed would gener- 
ally leave the power charge per train mile at not over ten 
cents. 'This is, of course, relatively very much better than 
street railway practice, but the units are far larger, the 
service easier in every way, the grades smaller and the 
work far more controllable and regular.